How is roughness measured?
The stylus method is used to measure and to describe the roughness of a surface. For the stylus method, a stylus tip is used at a constant speed over the surface of a part. With a technique of measure touch, the sensor of the device measure of roughness scans the surface point by point.
In fluid mechanics, the relative roughness of a surface is defined as the quotient of the absolute roughness over the length of the flow (eg the length of the body). The absolute roughness of a surface, on the other hand, is taken as the average height of its asperities,…
Roughness is the result of the microgeometric modification of a surface, caused by the intensive bombardment of this surface by projectiles (see section Definitions). Then appear: – cavities called “Hollows”.
A smooth surface, on the contrary, is easy to clean, due to its smooth profile. This is also one of the reasons why surface roughness plays a big role in industries such as food and pharmaceuticals. The surface is more hygienic and reduces the adhesion of bacteria.
It is important to remember that these two notions are different and completely independent of each other: – roughness is a physical characteristic.